Administration of the MapR-DB is done primarily via the command line (maprcli) or with the MapR Control System (MCS). Regardless of whether the MapR-DB table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter options. MapR-DB administration is associated with tables, columns and column families, and table regions.

The MapR Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight client applications and the MapR cluster. This section describes considerations when upgrading the service, how to modify configuration settings, and how to administer and manage the service.

ResourceManager Recovery Properties

The following table describes the configuration properties for ResourceManager
recovery:

Property

Description

yarn.resourcemanager.recovery.enabled

Enables the Resourcemanager to recovery based on the information
in the ResourceManager state store.

The default, set by configure.sh, is true.

yarn.resourcemanager.am.max-attempts

The maximum number of application attempts. This is a global
setting for all ApplicationMaster nodes.

You can configure an individual maximum number of application
attempts for each ApplicationMaster node, but this property sets a
global upper bound that overrides the individual node
configuration.

The default, set in yarn-default.xml, is 2.

mapreduce.am.max-attempts

The
maximum number of MapReduce application attempts. If this value is
larger than the value set by the ResourceManager, the
ResourceManager value will override this value. The default number
is set to 2, to allow at least one retry for AM. This
property is set in mapred-default.xml.

yarn.resourcemanager.fs.state-store.uri

URI pointing to the location of the FileSystem path where the
ResourceManager state is stored.

The default value is configured
to the path for the ResourceManager volume
(/var/mapr/cluster/yarn/rm/system).

If the FileSystem name is not provided, the system uses the
value specified in the fs.default.name specified in
the core-site.xml file.

yarn.resourcemanager.fs.state-store.retry-policy-spec

Specifies the retry policy for the MapR-FS client.

This policy is specified in pairs of values for the sleep time,
in milliseconds, and number of retries.

The class name of the state-store to be used for saving
application/attempt state and the credentials.

The available state-store implementations are
org.apache.hadoop.yarn.server.resourcemanager.recovery.ZKRMStateStore,
a ZooKeeper based state-store implementation, and
org.apache.hadoop.yarn.server.resourcemanager.recovery.FileSystemRMStateStore,
a state-store implementation based on MapR-FS.

The default, yarn-default.xml, is
org.apache.hadoop.yarn.server.resourcemanager.recovery.FileSystemRMStateStore.

yarn.resourcemanager.state-store.max-completed-applications

The maximum number of completed applications that the state
store retains, which is a number less than or equal to
${yarn.resourcemanager.max-completed-applications}.

The default value is 10000. This setting ensures that the
applications kept in the state store are consistent with the
applications in ResourceManager memory.

Any value larger than
${yarn.resourcemanager.max-completed-applications} is
reset to the default.

The value of this property affects ResourceManager recovery
performance.Typically, a smaller value optimizes performance for
recovery.

yarn.resourcemanager.zk-address

A comma-separated list of Host:Port pairs. Each corresponds to a
ZooKeeper server,
such as 127.0.0.1:5181,127.0.0.1:5181,127.0.0.1:5181.

These hosts are used by the ResourceManager to store state.

yarn.resourcemanager.zk-state-store.parent-path

The full path of the root znode
where ResourceManager state is stored. The default value
is/rmstore.

yarn.resourcemanager.zk-num-retries

Number of times the ResourceManager tries to connect to the
ZooKeeper server when the connection is lost.

The default value is 500.

yarn.resourcemanager.zk-retry-interval-ms

The interval between retries, in
milliseconds, when connecting to a ZooKeeper server. The default
value is 2000.

yarn.resourcemanager.zk-timeout-ms

The ZooKeeper session timeout in milliseconds. The ZooKeeper
server uses this configuration to determine session expiration.

Sessions expire when the server does not receive a heartbeat
from the client within the session timeout period. The default
value is 10000.

yarn.resourcemanager.zk-acl

ACLs that set
permissions on ZooKeeper znodes. The default value is
world:anyone:rwcda